public class LQB_code1_7 {
    public static void main(String[] args) {
        int n = 0; //香蕉的数量
        while (true){
            int a,b,c,d;
            a=b=c=d=0;
            if (n%5==1){
                a=n/5*4;
            }
            if (a%5==2){
                b=a/5*4;
            }
            if (b%5==3){
                c=b/5*4;
            }
            if (c%5==4){
                d=c/5*4;
            }
            if (d%5==0&&d!=0){
               break;
            }
            n++;

        }
        System.out.println(n);
    }
}
